Drive mechanisms including actuators are conventionally utilized to control the selective positioning of one or more members of a system. System design requirements dictate, and often limit, the specific design suitable for the application. In some environments, the system member to be controlled and/or manipulated is extremely thermally sensitive, such as infrared (IR) thermal imaging systems having movable shutters, including those operating in a true IR Dewer environment operating at cryogenic temperatures. Some conventional drive mechanisms are not suitable in such thermally sensitive systems where a thermal barrier needs to be maintained between a driving actuator and the driven device, such as to minimize or avoid stress, binding, wear and inconsistent operation of the system. Other conventional drive mechanisms have unreliable and inconsistent drive paths, and difficulty of meeting or staying within design tolerances. There is desired a drive mechanism that is reliably operable in thermally sensitive systems.